A thermodynamic basis for the electronic properties of molten semiconductors: the role of electronic entropy

Abstract

The thermodynamic origin of a relation between features of the phase diagrams and the electronic properties of molten semiconductors is provided. Leveraging a quantitative connection between electronic properties and entropy, a criterion is derived to establish whether a system will retain its semiconducting properties in the molten phase. It is shown that electronic entropy is critical to the thermodynamics of molten semiconductor systems, driving key features of phase diagrams including, for example, miscibility gaps.

Keywords:

• Entropy
• electronic entropy
• thermopower
• molten semiconductor

Acknowledgements

We would like to acknowledge the role of the Fannie and John Hertz Foundation for support of the researchers and Dr. Ali Sayir and the AFOSR for their financial support.

Notes

1. The reader is invited to consult Ref 5 for a discussion on electronic entropy. Electronic entropy is comprised of configurational electronic entropy (the entropy associated with localised electrons) and the electronic state entropy (the entropy associated with the size of the accessible state space of electrons in the system). Electronic state entropy represents the contribution of delocalised electrons as they manifest in the density of states near the Fermi level. This entropy proves to be quantitatively related to electronic transport properties as shown in Ref 5.